Finned tube protector



Sept. 20, 1966 R, A. DARLING FINNED TUBE PROTECTOR Filed July 1, 1964INVENTOR.

Raymond A. Darling MMK M FIG. 6

AGE/VT United States Patent 3,273,638 FINNED TUBE PROTECTOR Raymond A.Darling, 5306 E. 26th St., Tulsa, Okla. Filed July 1, 1964, Ser. No.379,673 5 Claims. (Cl. 165-134) This invention relates to improvementsin finned tubes and more particularly, but not by way of limitation, toa support for finned tubes so designed and constructed for supportingthe tube and protecting the radially extending fins on the outerperiphery thereof.

Fiuned tubes are frequently utilized in heat exchangers, and the like,wherein heat is transferred between fluids or other sub-substances.These finned tubes normally comprise a centrally disposed tube having aplurality of radially outwardly extending fins provided on the outerperiphery thereof and extending substantially throughout the lengththereof for facilitating or accelerating the rate of heat trans-fer. Thefins may be either a plurality of spaced individual annular discssecured to the outer periphery of the tube, or may be a continuousspiral or helical member extending around the tube. These finned tubesare often horizontally disposed in the heat exchanger with the oppositeends thereof connected to headers, or other ducts or parts of theapparatus. The tubes may be of a substantially great overall length andas a result tend to sag unless a support is provided intermediate theends thereof. Normally, the fins are constructed of a relatively thingauge material and do not have sufficient strength or rigidity towithstand the forces of a support member secured directly thereto. Inaddition, the outer periphery of the fins may be damaged by contact withthe fins of an adjacent finned tube if there is sufficient saggingwherein one tube is resting against a portion of a second tube.

Many solutions have been advanced for the problem of supporting thefinned tubes. In some instances, a portion of the fins may be removedwhereby the bare portion of the tube may be directly supported by thesupporting member. This is a particular disadvantage in the finned tubeshaving a continuous helical coil extending therearound since removal ofa portion thereof may result in the unwinding of the remaining portionof the fin. Additional solutions to the problem have been set forthwherein a band, or the like, is provided surrounding and contacting theperipheries of adjacent fins, such as disclosed in the Anthony J. RyderPatent No. 2,402,209, issued June 18, 1946, and entitled Support forFinned Tubes; the Karl Muhleisen Patent No. 1,748,140, issued February25, 1930, and entitled Means for Supporting and Holding Pipes in SpacedRelation to Each Other; and the William F. Matheny Patent No. 2,775,433,issued December 25, 1956, and entitled Finned Tube Spacing Supports.This type of support apparatus has disadvantages, however, in that theouter periphery of the fins may be damaged by the contact of the supportmember thereagainst, and the installation thereof is often tedious andtime consuming.

The present invention contemplates a novel support for finned tubesparticularly designed and constructed for protecting the fins whileeffectively supporting the tubes in radially spaced relationship. Thenovel finned tube protector comprises a pair of complementary arcuate orsemi-circular housings adapted to be disposed around the outer peripheryof the finned tube for encasing a plurality of adjacent radiallyextending fins. The inner diameter of each housing portion issubstantially equal to the outer diameter of the central tube portionand rests on the outer periphery thereof for providing a rigid supporttherefor. The outer diameter of each housing portion is slightly greaterthan the outer diameter of the fins, thus eliminating pressure on thefins during support of the I tubes. Each semi-circular housing sectionis provided with a circular inner periphery extending around slightlymore than one half the circumference of the central tube forfacilitating retaining of each half section in position around the tubewhile permitting easy removal of the sections from engagement with thecentral tube when desired. The protectors may be easily and quicklydisposed around the outer periphery of a plurality of adjacent fins aswell as readily removed therefrom. It is preferable to space thecomplementary housing sections throughout the length of the finned tubesin such a manner as to engage or contact the protectors disposed aroundthe adjacent finned tubes. In this manner, the protectors engage eachother to support the central tubes and maintain the finned tubes inradially spaced relationship to preclude contact between the outerperipheries of the radially extending fins of the adjacent tubes.

It is an important object of this invention to provide a novel finnedtube support particularly designed for efficiently supporting aplurality of the tubes in radially spaced relationship whilesimultaneously protecting the outer peripheries of the radiallyextending fins.

It is another object of this invention to provide a novel tinned tubeprotector particularly designed and constructed for engaging the outerperiphery of the central tube to provide a rigid support therefor.

Another object of this invention is to provide a novel finned tubeprotector adapted for precluding engagement or contact between theradially extending fins of adjacent finned tubes.

Still another object of this invention is to provide a novel finned tubeprotector which may be quickly and easily installed around the outerperipheries of the radially extending fins and readily removed fromdisposition therearound.

A further object of this invention is to provide a novel finned tubeprotector adapted to securely engage the outer periphery of the centraltube portion for retaining the protector in position around the finnedtube during utilization thereof.

A still further object of this invention is to provide a novel finnedtube support and protector which is simple and efiicieut in operationand economical and durable in construction.

Other and further objects and advantageous features of the presentinvention will hereinafter more fully appear in connection with adetailed description of the drawings in which:

FIGURE 1 is a front elevational view of a finned tube support sectionembodying the invention.

FIGURE 2 is a sectional elevational view taken on line 22 of FIGURE 1.

FIGURE 3 is an end elevational view taken on line 3-3 of FIGURE 1.

FIGURE 4 is a side elevational view of a finned tube having a pluralityof finned tube protector members embodying the invention disposedthereon, with a portion depicted in section for purposes ofillustration.

FIGURE 5 is a front elevational view of a modified form of a finned tubesupport embodying the invention.

FIGURE 6 is an end elevational view of the modified tube supportdepicted in FIGURE 5 as viewed from the open end thereof.

Referring to the drawings in detail, reference character 10 generallyindicates a finned tube structure comprising a central tube member 12having a spiral or helical radially outwardly extending coil 14 securedto the outer periphery thereof and extending substantially throughoutthe length thereof to provide a plurality of heat dispersing or heatdispensing fins, as is well known. A plurality of finned tube protectors16 are disposed around the outer periphery of the finned tube 10 and maybe longitudinally spaced therealong in a manner and for a purpose aswill be hereinafter set forth.

Each finned tube protector or support 16 comprises a pair ofsubstantially identical semi-circular half sections 18, and since thetwo half sections 18 are of an identical configuration and construction,only one will be set forth in detailed description. The semi-circularhousing or half-section 18 may be constructed from any suitable plasticmaterial, such as nylon, Teflon, or the like. Plastic materials of thistype are considered to be desirable since they are not effected by theusual temperature ranges within which finned tubes of this type arenormally utilized, and the characteristics of the materials renders theprotectors 16 easy to handle during installation or removal thereof.

The housing 18 comprises a pair of spaced side plates 20 and 22 havingthe inner bore or inner periphery 24 and 26, respectively, ofsubstantially the same diameter as the outer diameter of the centraltube 12. The sidewalls 20 and 22 are spaced apart by an outercylindrical portion 28 having an inner diameter slightly greater thanthe outer diameter of the fins 14. An inwardly directed semi-circularflange 30 is carried by the cylindrical outer member 28 and ispreferably substantially centrally disposed between the sidewalls 20 and22. The inner bore or inner periphery 32 of the rib 30 is of a diametersubstantially equal to the outer diameter of the central tube 12 and isin alignment with the bores 24 and 26 of the sidewalls 20 and 22 wherebythe sidewalls 20 and 22 as well as the inner rib or flange 30 engage theouter periphery of the tube 12 when the protector 16 is disposedthereon. In addition, the spacing between the rib 30 and each of thesidewalls 20 and 22 is preferably sufficient for receiving two adjacentfins 14 therebetween, but it is to be understood that the spacingtherebetween may be varied, as desired.

The outer ends 34 and 36' of the sidewall 20 are provided with anangular flange portion 38 and 40, respectively, whereby the bore 24extends through an arc greater than one half the circumference of theouter periphery of the central tube 12. In addition, the angular flange38 is provided with a tapered inner surface 42 and the angular flange 40is provided with a tapered outer surface 44 for a purpose as will behereinafter set forth. The sidewall 22 is provided with similar angularand tapered flange portions (not numbered) whereby the bore 26 isextended through an arc greater than one half the circumference of theouter periphery of the central tube 12. The material from which the halfsections 18 are constructed permits sufficient resilience or flexibilityto provide a spring-like action for the half sections during dispositionaround or removal from the outer periphery of the tube 12. Thus, thehalf sections may be easily disposed around the outer periphery of thetube 12, and the engagement of the bores 24 and 26 around an arc greaterthan half the circumference of the tube 12 securely retains the halfsections in position therearound without interference with the ease ofmanual rem-oval therefrom when desired. Thus, the half sections 18 aresupported by the outer periphery of the tube 12, and since the innerperiphery of the cylindrical portion 28 is of a diameter of the fins 14,there is no engagement between the fins and the cylindrical portion whenthe half sections 18 are disposed around the tube 12.

When the protectors 16 are to be disposed around the finned tube 10, apair of the half sections 18 may be normally disposed around the centraltube 12 for completely encasing a plurality of adjacent fins 14 at eachdesired spaced interval along the length of the finned tube 10, asclearly shown in FIGURE 4. One half section 18 may be disposed over thedesired portion of the fins 14 whereby two of the fins are disposedbetween the central rib 30 and the sidewalls 20 and 22, respectively, asshown in section in FIGURE 4. The half section 18 is inserted betweenthe fins in this manner sufliciently for the bores 24, 26

4 and 32 to engage the outer periphery of the central tube 12. Ashereinbefore set forth, the inner periphery of the cylindrical portion28 will not be in contact with the outer periphery of the fins 14, thusprotecting the fins from damage. A second half section 18 may then bedisposed around the remaining circumferential portion of the tube 12 andfins 14 in a similar manner. However, the sec 0nd half section 18 mustbe reversed with respect to the first half section 18 whereby thesidewall 20 of one half section will be in substantial alignment withthe sidewall 22 of the second half section 18. Thus, the inwardlytapered angular flange of one sidewall will be in engagement with theoutwardly tapered angular flange of the second sidewall, and vice versa,for a purpose as will be hereinafter set forth. Since the angularflanges 34 and 36 extend around the tube 12 through a distance greaterthan half the circumference thereof, there would be interference betweenthe abutting angular flanges of the two half sections. However, thetapered inner and outer sur-- faces of the angular flanges provide aclearance therebetween whereby the abutting portions of the halfsections will overlap around the outer periphery of the tube 12.

When the protectors 16 are disposed around the finned tube 10 having thehelical or spiral fins 14 as depicted therein, it will be readilyapparent that whereas the two half sections 18 will be in substantialalignment at one of the abutting edge portions thereof (not shown), thesecond abutting edge portions thereof will be offset, as shown at 46 inFIGURE 4, due to the helical disposition of the fins. However, if thefinned tube is provided with radially extending fins of the independentannular disc type, it will be apparent that both the abutting edgeportions of the two half sections encircling or encasing the tube 10will be in substantial alignment.

The two half sections 18 may be quickly and easily inserted between thefins 14 and disposed around the finned tube 10 for supporting the tubeand protecting the fins. Each half section is securely retained inposition by the gripping engagement thereof with the outer periphery ofthe central tube 12, and in addition, a rigid support is provided due tothe contact of the inner periphery of the half sections with the outerperiphery of the tube 12. It is preferable to provide a plurality of thesupport structures 16 for each finned tube 10, and the supports may belongitudinally spaced therealong as desired to provide suflicientsupport for the entire length of the finned tube. In addition, it ispreferable to space the supports 16 at substantially the same relativeposition on each of the finned tubes utilized in the heat exchanger (notshown), or the like. In this manner, any sagging of the finned tubeswill result in engagement between the support member 16 of the adjacentfinned tubes, thus precluding contact between the outer peripheries ofthe fins themselves. Since the support members 16 are supported from thecentral tube 12, and there is no engagement between the outer peripheryof the fins and the inner periphery of the cylindrical portion 28,'thefins are not only protected from engagement with the fins of an adjacentfinned tube, but also are protected from damage due to engagement withthe support structure itself.

Modified support structure Referring now to FIGURES 5 and 6, a modifiedsupport structure is depicted which is particularly designed andconstructed for utilization in heat exchanger, and the like, wherein thetemperature ranges are greater than those normally encountered in suchdevices. In the event the temperature range exceeds the temperaturesapplicable for the plastic materials hereinbefore set forth, it isdesirable to provide a support structure constructed from a suitablemetal, such as zinc, or the like. In this instance, the finned tubesupport is generally similar to that hereinbefore set forth, andcomprises a pair of identical half sections 50 which may be disposedaround the finned tube 10 for encasing a plurality of adjacent fins 14.The half section 50 comprises a semi-cylindrical outer housing 52 havingan inner diameter slightly greater than the outer diameter of the fins14. An inwardly directed semicircular rib or flange 54 is provided inthe housing 52 and the inner bore or inner periphery 56 thereof is of adiameter substantially equal to the outer diameter of the central tube12.

The outer ends 58 and 60 of the rib 54 are provided with angular flanges62 and 64, respectively, which extend the inner periphery 56 through anarc greater than half the circumference of the tube 12. In this manner,the rib 54 engages a portion of the outer periphery of the tube 12 whichis greater than half the circumference thereof for securely retainingeach half section 50 in position around the central tube 12. Inaddition, the rib 54 is so spaced within the housing 52 as to be incloser relation to one end thereof than the other, as clearly shown inFIG- URE 6. The rib 54 is so spaced within the housing 52 where-by therib 54 of one-half section 50 will be off-set from the rib 54 of thecomplementary half section 50 as will be hereinafter set forth when thetwo half sections are disposed around the finned tube for encompassingthe outer periphery of the fins 14.

The half sections 50 may be easily disposed around the finned tube 10 inmuch the same manner as set forth in the first embodiment. The materialfrom which the half sections are constructed is sufficiently flexible orresilient to provide a substantially spring-like action in order thatthe inner bore 56 may be readily positioned around or removed from theouter periphery of the central tube 12. One half section may be disposedaround the finned tube 10 by inserting the rib 54 between a pair ofadjacent fins 14 and moving the inner bore 56 into engagement with theouter periphery of the central tube 12. The engagement between the 'bore56 and the greater portion of the outer circumference of the centraltube 12 securely retains the half section 50 in position therearound. Asecond half section 50 may then be similarly disposed around theremaining circumference of the finned tube 10. However, the second halfsection 50 must be reversed with respect to the first half section.Thus, the rib 54 of one half section will be disposed in the spacebetween one pair of adjacent fins 14 whereas the rib 54 of the secondhalf section will be disposed in the next succeeding space between thenext succeeding pair of fins. In this manner there will be nointerference between the ribs 54 of the complementary half sectionswhich encompass the outer periphery of the finned tube 10.

Of course, it is preferable to space a plurality of the complementaryhalf sections 50 throughout the length of the finned tubes 10, ashereinbefore set forth, for providing an efficient support therefor.Furthermore, the half sections 50 may be utilized with finned tubeshaving the independent disc type fins as well as the helical or spiralfins depicted herein.

From the foregoing, it will be apparent that the present inventionprovides a novel support and protector for finned tubes which may bequickly and easily installed on or removed from the finned tubes. Thenovel protector device is particularly designed and constructed forefliciently supporting the finned tubes in radially spaced relationshipwhile simultaneously protecting the outer peripheries of the fins fromdamage due to engagement with the support structure or from engagementwith the fins of an adjacent finned tube. The novel protector structuremay be utilized with substantially any type of finned tube, and issimple and eflicient in operation and economical and durable inconstruction.

Changes may be made in the combination and arrangement of parts asheretofore set forth in the specification and shown in the drawings, itbeing understood that any modification in the precise embodiment of theinvention may be made within the scope of the following claims, withoutdeparting from the spirit of the invention.

What is claimed is:

1. In combination with a finned tube including a central tube having aplurality of radially extending fins on the outer periphery thereof, aprotector device comprising a pair of semi-circular housing sectionsremovably securable to the central tube in end to end relationship forencasing a plurality of adjacent fins, each of said semi-circularhousing sections comprising a plurality of spaced radial rib members, asemi-cylindrical outer surface provided on the outer extremity of theradial rib members and having an inner diameter slightly greater thanthe outer diameter of the fins, each of said rib members provided withan inner periphery of 'a diameter substantially equal to the outerdiameter of the central tube, angular flange means provided on portionsof said rib members for extending the inner periphery thereof through anarc greater than one half the circumference of the central tube forfacilitating securing of each housing section therearound, and taperedmeans provided on the angular flange means for precluding interferencebetween the rib members of the complementary pair of semi-circularhousings encasing the fins.

2. In combination with a finned tube including a central tube having aplurality of radially extending fins on the outer periphery thereof, afin protector comprising a pair of complementary semi-circular housingscooperating for encasing a plurality of adjacent fins, each of saidhousings comprising a pair of spaced semi-circular sidewalls having aninner periphery of a diameter substantially equal to the outer peripheryof the central tube, a substantially cylindrical outer housing providedaround the outer extremity of the sidewalls and having an inner diameterslightly greater than the outer diameter of the fins, an angular flangeprovided on the outer ends of each sidewall for extending the innerperipheries thereof through an are greater than one half thecircumference of the central tube, tapered means provided on eachangular flange for precluding interference between the flanges of thecomplementary pair of semi-circular housings encasing the fins, aradially inwardly directed rib carried by the outer housing andsubstantially centrally disposed between the spaced sidewalls, and saidrib having an inner periphery of a diameter substantially equal to theouter diameter of the central tube for cooperating with the sidewallsfor supporting of the tube.

3. In combination with a finned tube including a central tube having aplurality of radially extending ribs on the outer periphery thereof, aremovable fin protector comprising a pair of complementary semi-circularhousings cooperating for encasing a plurality of adjacent fins, each ofsaid semi-circular housings comprising an arcuate outer housing havingan inner diameter slightly greater than the outer diameter of the fins,a radially inwardly directed rib member carried by the outer housing andhaving an inner diameter substantially equal to the outer diameter ofthe central tube for engagement therewith, and an angular flangeprovided on the outer ends of the rib for extending the inner peripherythereof through an are greater than one half the circumference of thecentral tube for facilitating securing of the complementary semicircularhousings around the central tube.

4. In combination with a finned tube including a central tube having aplurality of radially extending ribs on the outer periphery thereof, aremovable fin protector as set forth in claim 3 wherein the rib memberis disposed in closer relation with one end of the outer housing thanthe other end thereof whereby interference between the ribs of thecomplementary semi-circular housings is precluded.

5. In combination with a finned tube including a central tube having aplurality of radially extending fins on the outer periphery thereof, aremovable protector device comprising a pair of semi-circular housingsections removab-ly securable to the central tube in end to endrelationship for encasing a plurality of adjacent fins, each of saidsemi-circular housing sections comprising radial rib means, asemi-cylindrical outer surface provided on the outer extremity of therib means and having an inner diameter slightly greater than the outerdiameter of the fins, said rib means provided with an inner periphery ofa diameter substantially equal to the outer diameter of the centraltube, angular flange means provided on said rib means for extending theinner periphery thereof through an are greater than one half thecircumference of the central tube for facilitating securing of eachhousing section therearound, and means for precluding interferencebetween the rib means of the complementary paid of semi-circularhousings encasing the fins.

References Cited by the Examiner UNITED STATES PATENTS 2,166,808 7/1939Flindt 16567 X 3,012,761 12/1961 Gardner et al 165-69 FOREIGN PATENTS697,477 9/1953 Great Britain.

ROBERT A. OLEARY, Primary Examiner.

CHARLES SUKALO, Examiner.

M. A. ANTONAKAS, Assistant Examiner.

3. IN COMBINATION WITH A FINNED TUBE INCLUDING A CENTRAL TUBE HAVING APLURALITY OF RADIALLY EXTENDING RIBS ON THE OUTER PERIPHERY THEREOF, AREMOVABLE FIN PROTECTOR COMPRISING A PAIR OF COMPLEMENTARY SEMI-CIRCULARHOUSING COOPERATING FOR ENCASING A PLURALITY OF ADJACENT FINS, EACH OFSAID SEMI-CIRCULAR HOUSINGS COMPRISING AN ARCUATE OUTER HOUSING HAVINGAN INNER DIAMETER SLIGHTLY GRATER THAN THE OUTER DIAMETER OF THE FINS, ARADIALLY INWARDLY DIRECTED RIB MEMBER CARRIED BY THE OUTER HOUSING ANDHAVING AN INNER DIAMETER SUBSTANTIALLY EQUAL TO THE OUTER DIAMETER OFTHE DENTRAL TUBE FOR ENGAGEMENT THEREWITH, AND AN ANGULAR FLANGEPROVIDED ON THE OUTER ENDS OF THE RIB FOR EXTENDING THE INNER PERIPHERYTHEREOF THROUGH AN ARC GREATER THAN ONE HALF THE CIRCUMFERENCE OF THECENTRAL TUBE FOR FACILITATING SECURING OF THE COMPLEMENTARY SEMICIRCULARHOUSINGS AROUND THE CENTRAL TUBE.